New 3D-Printed 944 Timing Belt Tensioner Tool

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Tom
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Here is our all-new 3D-printed timing belt tensioning tool for the 944.

Carpokes 944 Timing Belt Tensioner.stl
(This is the version most people will want. You need at least one post on Carpokes to download files!)


Carpokes 944 Tensioner with Power Brim.stl
(See post #53 in this thread)

Carpokes 944 Tensioner with Heat Set Threads.stl
(See post #143 in this thread)



[Note: if you cannot download the .stl above, be sure you register and account and are logged in with at least 1 post on Carpokes. If, after that, you still have problems, feel free to email me at admin@carpokes.com.... ]



Image


The basic idea is that it relies on a torque wrench to measure how tight the belt is. The tool has two small pointers that correspond to the new and used belt factory tensioning specs. The appropriate pointer should line up with the guiderail on the water pump when the torque wrench reaches 7 ft. lbs. (84 inch pounds).

Although I’ve tested it with multiple torque wrenches and calibrated the pointers to match the factory tool, I’d still consider this a beta version until we have several people actually print it and use it (i.e., use common sense and use at your own risk, etc., etc.) My plan is to update the tool after more real-world use, but at least in my garage, on my test motor, it works remarkably well. [May '23 edit, all feedback to date has been good, so no current plans to update the tool.]

The one in the video is posted in ABS with 100% infill and 4mm wall thickness. PLA should also work fine, if not better. The model has holes for six sheet metal screws (No. 6 screws 1.5 inches long) to give the tool the mechanical strength it needs to hold together. The tab that applies pressure to the belt is prone to snapping off without the screws, and the drive socket is prone to cracking apart. The screws seem to solve all that, as long as you don’t go past 7 ft. lbs. with the wrench. You may be able to get away without the screws if you use super hard plastics, like NylonX, etc., but I haven’t test that yet.

See it in action in the video below! All feedback encouraged!


You need at least one post on Carpokes to see and download files.


#1

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stitch2k1
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I like this a lot. Definitely going to share this with anyone I see who's trying to do it just by hand. I would like to try one to compare with the Arnnworx tool I have, but I don't have a printer sadly. I probably ought to invest in one next year.

My inner aircraft mx has to ask, were any of the torque wrenches you tried calibrated by a shop and how many did you use?


1991 944S2
2000 540iT/6
Insta: stitch2k1

#2

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Tom
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naesjr wrote: Fri Jul 01, 2022 8:10 pm I like this a lot. Definitely going to share this with anyone I see who's trying to do it just by hand. I would like to try one to compare with the Arnnworx tool I have, but I don't have a printer sadly. I probably ought to invest in one next year.

My inner aircraft mx has to ask, were any of the torque wrenches you tried calibrated by a shop and how many did you use?
Thanks! As always, for good active Carpokeans, I'll do my best to print them for folks. :)

Two of the wrenches had been calibrated maybe 2 or 3 years ago, and the one in the video was brand new (but a 4% cheapy from HF). I was going for a tool that would work with things people already had in their toolbox, like questionably calibrated torque wrenches, or could buy on the cheap like that HF wrench for $18.99. :)


#3

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stitch2k1
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Tom wrote: Fri Jul 01, 2022 8:16 pm
naesjr wrote: Fri Jul 01, 2022 8:10 pm I like this a lot. Definitely going to share this with anyone I see who's trying to do it just by hand. I would like to try one to compare with the Arnnworx tool I have, but I don't have a printer sadly. I probably ought to invest in one next year.

My inner aircraft mx has to ask, were any of the torque wrenches you tried calibrated by a shop and how many did you use?
Thanks! As always, for good active Carpokeans, I'll do my best to print them for folks. :)

Two of the wrenches had been calibrated maybe 2 or 3 years ago, and the one in the video was brand new (but a 4% cheapy from HF). I was going for a tool that would work with things people already had in their toolbox, like questionably calibrated torque wrenches, or could buy on the cheap like that HF wrench for $18.99. :)
Like I commented in the other thread (not seeing the talk of your torque wrenches) I've seen one of those cheapo HF 1/4" wrenches calibrate better than a Snap-on one. I don't believe in any engineering that makes any better than the others in any department other than making you feel fancy. I will probably consider a nicer digital torque wrench when holiday sales come around, since I'm gonna be doing more engines in the future. 100% getting it checked out yearly.

And the inaccuracy of the HF one is probably still better than the inaccuracy of a twist or a clicker tool anyway. So it's better than nothing which is what makes this great.
Plans for a balance shaft tool next? Cause that seems to be even more of a PITA. I am still struggling to dial out the belt whine in my S2 and I did it dead to factory tolerances, with it right on the loose side of the scale.


1991 944S2
2000 540iT/6
Insta: stitch2k1

#4

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PTRogers85
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Thanks Tom! I'll definitely have to print one, good thing I recently bought a spool of ABS 😁


#5

medic26bfd
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Joined: Sat Jul 02, 2022 11:12 am
Need to print this.


#6

Pershe944
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Really looking to be able to try this out!


#7

Nathankel
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great help, thank you very much for this great job. the best is to print it in ABS?


#8

papasmurf
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Joined: Sat Jul 02, 2022 1:50 pm
Great job on designing this....this will potentially save some 944's from having a belt being too tight/loose and having it being catastrophic. I previously downloaded and printed the oil cooler alignment tool when I redid the seals on my car and it worked great (credit to whomever designed it) and this will no doubt be something I have printed and added to the tool box.


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JoeBudapest
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Hello,
I will test it on my early 944. Thanks for the tool. :thumbup:


#10

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